10.5 library(threadutil): Interactive thread utilities
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Availability::- use_module(library(threadutil)).(can be autoloaded)
Source[det]tspy(:Spec)
[det]tspy(:Spec, +ThreadOrClass)
Trap the graphical debugger on reaching Spec. The predicate tspy/0 enabled debug mode in all threads using tdebug/0 while tspy/1 enables debug mode using tdebug/1.